1. Field of the Invention
One embodiment of the present invention relates to a display device, and particularly to a flexible display device capable of performing display along a curved surface. One embodiment of the present invention relates to an input and output device and particularly to a flexible input and output device capable of performing display along a curved surface.
Note that one embodiment of the present invention is not limited to the technical field. The technical field of one embodiment of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. One embodiment of the present invention relates to a process, a machine, manufacture, or a composition of matter. Specifically, the technical field of one embodiment of the present invention disclosed in this specification includes a semiconductor device, a display device, a light-emitting device, an electronic device, a method for driving any of them, and a method for manufacturing any of them.
2. Description of the Related Art
In recent years, a flexible device in which a semiconductor element, a light-emitting element, and the like are provided over a flexible substrate has been developed. Typical examples of the flexible device include, as well as a lighting device and an image display device, a variety of semiconductor circuits including a semiconductor element such as a transistor.
As a method of manufacturing a semiconductor device including a flexible substrate, the following technique has been developed: a semiconductor element such as a thin film transistor (TFT) is formed over a support substrate (e.g., a glass substrate or a quartz substrate), and then the semiconductor element is transferred to a flexible substrate. In this technique, a step of peeling a layer including the semiconductor element from the support substrate is needed.
Patent Document 1 discloses a peeling technique using laser ablation as follows. A separation layer formed of amorphous silicon or the like is formed over a substrate, a layer to be peeled is formed over the separation layer, and the peeled layer is bonded to a transfer body with a bonding layer. The separation layer is ablated by laser irradiation, so that separation is generated in the separation layer.
Patent Document 2 discloses the following peeling technique: a metal layer is formed between a substrate and an oxide layer and peeling is generated at an interface between the oxide layer and the metal layer by utilizing weak bonding at the interface between the oxide layer and the metal layer, so that a layer to be peeled and the substrate are separated from each other.